Posted by erika on Saturday, February 4, 2012 at 11:24am.
a steamboat travels 9 miles up a river in 3 hours and returns the same distance down the river in 2 hours. find the speed of the boat in still water and the rate of the current.
- algebra - Reiny, Saturday, February 4, 2012 at 11:31am
speed of boat in still water --- x mph
speed of current --- y mph
distance up river = time (rate) = 3(x-y) = 9
3x-3y = 9
distance down river = 2(x+y) = 9
multiply first by 2
2x-2y = 6
2x+2y = 9
4x = 15
x = 15/4 = 3.75 mph
then in x-y = 3
3.75-y = 3
y = .75 mph
the boat has a speed of 3.75 mph in still water, and
the current has a speed of .75 mph
speed with the current = 4.5
distance = 2(4.5) = 9
speed against current = 3
distance = 3(3) = 9
- algebra - Anonymous, Monday, April 25, 2016 at 1:09am
The current of a river is 2 miles per hour. A boat travels to a point 8 miles uptream and back in a total of 3 hours. What is the speed of the boat in still water
Answer This Question
More Related Questions
- algebra - A boat traveling on the Snake River travels 24 miles upstream in 3 ...
- math help!! - A boat travels down the river in 2.9 hours. The return trip up ...
- help math - A boat travels down the river in 3.0 hours. The return trip up river...
- help math!!! - A boat travels down the river in 2.3 hours. The return trip up ...
- math - A boat is rowed down a river a distance of 16 miles in 2 hours and it is ...
- math - A boat travels down the river in 2.8 hours. The return trip up river ...
- math - A boat travels down the river in 2.6 hours. The return trip up river ...
- Algebra 2 - The excursion boat on the river takes 2½ hours to make the trip to a...
- MATH - In still water, a speed boat travels 5 times faster than the current of ...
- Pre Calculus - A motorboat travels 48 miles down a river in the same time it ...